Alternating-current magnet and the like.



H. A. SEDGWICK.

ALIERNATING CURRENT MAGNET AND THE LIKE.

APPLICATION FILED FEB. 20, I915.

Patented Nov. 27, 1917.

UNITED STATES PATENT oEEIoE.

HARRY A. SEDGWICK, or MIL AUKEE, wr-scoivsrnAssioivo t To THE CUTLER- HAMMER MFG. 00., or MILWAUKEE, WISCONSIN, A CORPORATION oEwIsooNsIN.

A-LrERnArnvs-ounitiin'r MAGNET AND THE LIKE.

Specification of Letters Patent.

Patented Never; 1917.

Application filed February 20,.1915.- SerialNo. 9,630.

To all whom it may concern:

Be it known that I, HARRY A; SEDewIoK, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and lowing is a full, clear, concise, and exact descript1on,reference being had to the accompanying drawing, forming a part of this specification.

This invention relates to improvements in alternating current magnets, magneticswitches and other; devices having attracted parts which are pivotally mounted.

In practice, where a pivoted lpart-is at tracted by an alternating current magnet there is atendency forsuchupart to vibrate 011 its pivot and the degree of'vibration is materially increased by wear on the engaging pivotal parts. These conditions obtaineven where shading coils or other means are provided to minimize vibration ofathe attracted part and the chattering: of the attracted part on its pivot, is often very objectionable, especially after the pivotal parts have become worn.-.

This invention has among its objects to provide means to eliminate, or at least materially reduce,'the vibration "of the attracted parts of alternating current devices at the pivotal points thereof.

A further object is toprovide means for the aforesaid purpose which will compensate for wear on the engaging pivotal. parts.

Other objects and advantages will hereinafter appear.

The accompanying drawing illustrates an alternating current switch provided with one form of the invention and the same will now be described, it being understood that the invention is not limited to the specific form thereof selected for the purpose of illustration and is adapted for use in other relations than that depicted.

The single view in the accompanying drawing is a side elevation of the switch.

The switch illustrated is of conventional form and of the double-pole type, the second pole being identical with that appearing in the drawing. Briefly set forth the switch has two movable contact arms 1 operable by an alternating current magnet 2 to cooperate with stationary contacts 3. The magnet 12 is mounted in a suitable frame 4 fixed to a panel 5 and has a pivoted armature-6 to which the two switch armsl are -rig dly' secured as bymeans of bolts 7. The arma ture member-6 has ahub 8 (dotteddines) revoluble on a shaft 9 supported in a'clamping bearing 10 provided thereforgon the magnet frame. Thus upon attraction of the armature to close the switch the-hub 8 will turn on the shaft9 and in consequencesubject botlr'of said parts to wear; In practice,

the hub 8 is preferably bifurcated :or cutaway to-straddlethe clamping bearing-10 of theshaft 9.

The means illustrated to prevent vibration of the armature on its pivot consists of a hooked member 11 havinga single point bearing 12 on the forward side of the hub 8 and connected by. a tension spring 13 toa fixed part 14. As illustrated, the partl i comprises'a right-angle plate secured by a; bolt 15 prlmarlly provided to secure the magnet frame to the supporting panelfi The bearing end of the hooked member is preferably rounded and provided with a concave bearing surface onthe hub 8 forfre'edom of movement while said hooked member as" a whole is so formed as to clearthe hub except at the aforesaid bearing: point. Further, the bearing-point of :the hook and the fixed end of the spring 13are preferably sodisposed that the line of force will intersect or approximately intersect the axis of the armature 6. However,-as will be obvious, pivotal movement of the armature member will. shift thebearing of the hooked memher and this will slightly vary the relation of the line of force with respect to the axis of the armature. Where the hub is bifurcated to straddle the clamping bearing of the shaft 9 then the tension device just described is prefrably duplicated for the two sections of the hub.

It will thus be observed that the tension device exerts on the armature at all times a force directed substantially radially to its axis. Moreover, it will be observed that this force is so directed as to complement the magnetic force exerted upon the armature at its point of fulcrum. Thus the tension device serves at all times to maintain the pivotal parts of the armature in firm engagement and thereby tends to eliminate any chattering of the engaging pivotal parts. Moreover, the tension device is inherently adjustable to compensate for initial loose fitting of the pivotal parts and for subsequent wear thereon, thereby insuring permanency of its effectiveness.

As employed in the switch illustrated the primary purpose of the tension device is to maintain firm engagement of the pivotal parts and to this end said device is so designed as to divide equally any tendency which it may have to assist or oppose operation of the armature. In other words, the arrangement is such that in operation of the switch the line of force exerted by the tension device is shifted across the axis of the armature and to equal degrees on opposite sides thereof. However, it will be readily apparent that the tension device may, if desired, be so arranged as to exert force in other relations with respect to the axis as, for example, to always bias the switch to open position or to exclusively assist the magnet in closing the switch.

As above set forth, the invention may be embodied in various different forms and employed in other relations.

What I claim as new and desire to secure by Letters Patent is:

1. The combination with an alternating current magnet and armature therefor mounted upon a rigid pivot pin, of biasing means engaging said armature to curtail chattering of its pivot parts, said means and said armature having an anti-friction bearing therebetween concentrating the biasing force of the former upon the latter.

2. The combination with an alternating current magnet and pivoted armature therefor, of a resilient device including a part having a pivotal bearing upon said armature, said device exerting a force upon said armature through said pivotal bearing and in a direction substantially radially of the axis of said armature.

8. The combination with an alternating currentmagnet and pivoted armature there for, of a resilient device having a fixed part and a pivotal connection with said armature, said device exerting a biasing force upon said armature, through said connection, substantially radially of the pivotal axis of said armature but variable with respect to said axis according to the position ing of said connection by said armature.

a. The combination with an alternating current magnet and pivoted armature there for, of a resilient device having a fixed part on one side of the pivotal axis of said armature and a pivotal connection with said armature on the opposite side of said axis, whereby said device exerts a biasing force upon said armature substantially radially of its axis but variable with respect to said axis by movement of said connection by said armature.

5. The combination with an alternating current magnet provided with a supporting frame, a rigid pivot rod carried by said frame and an armature mounted on said rod, of a spring having one end connected to a fixed part on one side of the pivotal. axis ofsaid armature and a hooked member for connecting the other end of said spring to said armature on the opposite side of said axis, said spring exerting a biasing force upon said armature substantially radially of said pivot rod, and said hooked member having a rounded end portion fitting into a concave bearing in said ar1na ture.

In witness whereof, I have hereunto subscribed by name in the presence of two witnesses.

HARRY A. SEDGWICK.

Witnesses:

TEKLA BAST, L. A. WATSON.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. 0. 

